The invention relates to novel phosphono-s-triazines in which the phosphono groups are further substituted with a primary hydroxyl-containing hydrocarbon radical.
Flame resistance in synthetic resins, in particular polyurethane resins, can be increased by the addition of phosphorus-containing compounds. In most cases, such compounds are blended into the resins. Unfortunately these phosphorus-containing compounds leach out of the resins into which they have been blended.
What is needed is a phosphorus-based flame retardant which can be incorporated into a polyurethane resin. Phosphorus-containing compounds which further contain reactive primary hydroxyl groups would allow such incorporation. The problem is that primary hydroxyl groups are highly reactive with phosphorus. Thus attempts to prepare phosphorus compounds containing reactive primary hydroxyl groups usually result in the reaction of the primary hydroxyl groups with the phosphorus itself. What is further needed is a process for preparing stable phosphorus compounds with the reactive primary hydroxyl groups.